What’s Vulnerable › Vulnerabilities

CVE-2026-18675: Kong Mesh: control plane denial of service via a malformed dataplane token with a non-string JWT kid

• Severity: medium (CVSS 5.3 v4.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.6% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-08-12 · updated 2026-10-23
• Weakness: CWE-248

Description

The dataplane token validator in kuma-cp performs an unchecked Go type assertion on the JWT kid header. A token whose kid is a JSON number decodes as a float64 and triggers a runtime panic before any signature, claims, or authorization check runs. The panic terminates the entire kuma-cp process, HTTP API, the health and readiness endpoints, and xDS. Unauthenticated access to the dataplane gRPC server can trigger the crash with a malformed token A single request is a transient interruption; sustaining an outage requires repeated requests.

Affected products

• Kong Inc. Kong Mesh: before 2.7.29; from 2.8.0 before 2.9.19; from 2.10.0 before 2.11.18; from 2.12.0 before 2.12.14; from 2.13.0 before 2.13.10; from 2.14.0 before 2.14.2 — fixed in 2.11.18, 2.12.14, 2.13.10, 2.14.2, 2.7.29, 2.9.19

How to fix

Upgrade to a fixed version: Kong Inc. Kong Mesh 2.11.18, 2.12.14, 2.13.10, 2.14.2. Check the vendor advisory for mitigations.

References

• https://developer.konghq.com/mesh/changelog/
• https://github.com/kumahq/kuma/pull/17465
• https://github.com/kumahq/kuma/pull/17467
• https://github.com/kumahq/kuma/pull/17468
• https://github.com/kumahq/kuma/pull/17469
• https://github.com/kumahq/kuma/pull/17470
• https://github.com/kumahq/kuma/pull/17471
• https://github.com/kumahq/kuma/pull/17472
• https://github.com/kumahq/kuma/security/advisories/GHSA-5mxq-7xq4-3vx8

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